Let's not mince words. If Israel does a preemptive strike on Iran's nuclear facilities it is the aggressor starting the war. Iran the victim would be completely justified in retaliating. Iran has never started a war. At last count Israel has started six: five with Lebanon and the 1967 war where Israel fired the first shots Iran has never threatened Israel with a nuclear frist strike.
from the article: Lieberman: Iran poses most dangerous threat to world order